SING stands for 'Send ICMP Nasty Garbage.' It is a tool that sends ICMP
packets fully customized from command line.  It's main purpose is to
replace and complement the ping command, adding certain enhancements as
fragmentation; send and receive spoofed packets; send many ICMP
information types (echo as the old ping, address mask, timestamp, and
router discovery) and errors (redirect, unreach, and time exceeded); and
send monster packets.  It also supports loose and strict source routing
and record routing.
